Light sources for Wet Plate/Dry Plate

Discussion in 'Alternative Processes' started by TheFlyingCamera, Apr 11, 2007.

  1. TheFlyingCamera

    TheFlyingCamera Membership Council Council

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    It is my understanding that wet plate and dry plate have similar approximate speeds- around 1 ASA. I also understand that wet plate needs light that is rich in UV, and dry plate being orthochromatic is also biased in the color spectrum. This being said, what are good light sources other than full sunlight, and how much of it do I need to get 1 second or less exposures? I currently have some 750 ws studio strobes, and I know at full power, I'd be lucky to hit f4 at five feet if I assume ASA 1 for my film speed. F4 is not enough DOF for a portrait on 5x7 or full-plate. Any suggestions? Can I do it with enough hotlights? What kind of strobe power do I need, and will they put out enough of the right kind of light? If fluorescents, what kind of total wattage do I need?
     
  2. JG Motamedi

    JG Motamedi Member

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    I have had good results from fluorescents. I use three banks with a total of eight 21" 5500K 55W compact fluorescent bulbs for aquariums (http://ahsupply.com/). A head and shoulders ambrotype portrait with these lights is a two second exposure at f4. This is more or less my exposure with north-light. I once tried using 10000K bulbs, but the speed difference wasn't worth the cost of replacing the bulbs. An added bonus of the 5500K lights is that they work decently (albeit a bit slowly) for alt. process printing and for general studio work in color.

    Also, almost all the people I know working with wet-plate do their portraits wide open, so don't expect much in the way of DOF if using collodion. It is a different way of thinking; with Collodion DOF is best measured in inches, not feet.
     
    Last edited by a moderator: Apr 11, 2007